code: def get_or_create(session_uuid: str):
      disk_key = DiskIndex.get(session_uuid)
  
      if not disk_key:
          d = DiskModel()
          d.save()
          DiskIndex.set(session_uuid, d.key)
  
          dp = DiskPreferencesModel()
          dp.save()
          DiskPreferencesIndex.set(session_uuid, dp.key)
  
          return DiskAnalysis(d)
  
      return DiskAnalysis(disk_key.load())
  
imports: from typing import Dict, Any
  from fastapi import Request
  from fastapi.responses import JSONResponse
  from labml_db import Model, Index
  from labml_db.serializer.pickle import PickleSerializer
  from labml_app.logger import logger
  from labml_app.enums import COMPUTEREnums
  from ..analysis import Analysis
  from ..series import SeriesModel, Series
  from ..series_collection import SeriesCollection
  from ..preferences import Preferences
  from ..None import helper
label_desc: Use image node_id 4 for calling the DiskAnalysis obj's underlying member method code with example usage: obj.get_or_create(session_uuid) and returns: DiskAnalysis, DiskAnalysis